The historical scholar will find nothing new in the following pages; but I have thought it worth while to tell to the general reader a story worth the telling, and to explain not only the details, but the wider bearings also, of a great crisis in European history, no satisfactory account of which exists, I believe, in English, and the two hundredth anniversary of which is now upon us. My principal authorities are "Sobieski's Letters to his Queen," edited by Count Plater, Paris, 1826; Starhemberg's "Life and Despatches," edited by Count Thürheim, Vienna, 1882; "Campaigns of Prince Eugene, of Savoy," Vienna, 1876, etc.; Schimmer's "Sieges of Vienna;" Von Hammer's "History of the Turks;" Salvandy's "History of Poland;" "Memoirs of Eugene," by De Ligne; "Memoirs of Charles, Duke of Lorraine, and his Military Maxims," published late in the seventeenth century; "Works of Montecuculi;" De la Guillatière's "View of the Present State of the Turkish Empire, etc.," translated, London, 1676, etc.